Well investors will sometimes have a home owner do a quit claim deed. Then assume the payments. Basically, until payment is received on the property you could effect your grandma if not paid on time. Sometimes it's considered a DIL-Deed in Lieu of Foreclosure. Investors may consider it a sandwich lease as well.
The hitch is grandma is on the hook until the cash is received to pay off the note she created. FHA is a good way to go for a low down payment unless your a vet. So it would be done as a purchase sale. With FHA it's 3.5% of purchase price down.
Example:
Purchase Price $200,000 x .03%=$6,000 down payment
200,000/360=$556 principal
200,000 x .04%=$8,000/12=$667 interest rate @ 4%
taxes 2,000/12=$167
ins $2,000/12=$167
Total house payment $1,557 per month
They will go from between 42 to 50% on your DTI-Debt to income ratio
The DTI is gathered from your secured assets- house, car, credit cards, student loans
A good FHA loan officer shouldn't have a hard time qualifying you if your earnings are easily verified and you have a good banking track record. They will want paycheck stubs and bank statements.